Abstract
Purpose :
We investigated change from baseline to week 12 in contrast sensitivity (CS), visual acuity (VA), central retinal thickness (CRT) and vision-related quality of life in subjects with recalcitrant nAMD switched from long-term ranibizumab treatment to aflibercept.
Methods :
In this prospective, investigator masked, single-center study, 40 randomly selected nAMD patients with persistent fluid following at least 3 ranibizumab injections in the previous 6 months were switched to aflibercept therapy with 3 consecutive monthly loading doses (week 0, 4, and 8). The primary efficacy measure was change from baseline to week 12 in CS measured using the Pelli-Robson Chart. Change from baseline in best-corrected visual acuity (BCVA), CRT, and National Eye Institute 25-Item Visual Function Questionnaire (NEI VFQ-25) score were recorded.
Results :
Forty-nine eyes of 40 patients (baseline VA>6/120, mean age 80.2 years) with nAMD were evaluated. A mean of 28.2±22.1 (range 3–86) ranibizumab injections were administered prior to initiation of aflibercept treatment. The mean CS increased from 1.32±0.20 log units at baseline to 1.40±0.18 at week 12 (p=0.00079), while the mean VA was maintained stable over the study period (logarithm of the minimum angle of resolution [logMAR] VA 0.53±0.44 at week 12 compared to 0.52±0.41 at baseline). Mean CRT decreased to 334±85µm at week 12 from 356±103µm at baseline, a statistically significant decrease of 21µm (p=0.004). There was an associated relationship between change in CS and change in CRT (R2=0.30, p=0.000046). Twenty-six of 40 (65%) patients experienced an overall improvement in NEI VFQ-25 score; 8 patients (20%) experienced no change; 6 patients (15%) experienced a decrease. The observed average 2-letter improvement in CS from baseline is broadly equivalent to a 5-letter VA improvement.
Conclusions :
Contrast sensitivity significantly improved and CRT significantly decreased from baseline to week 12 in patients switched to aflibercept from ranibizumab. Vision-related quality of life improved in two-thirds. Inclusion of CS as an independent efficacy endpoint in prospective nAMD studies may yield a more complete understanding of visual outcomes than that obtained using VA measurement alone.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.